The present invention relates to a device for dispensing different types of fuel from a single fuel dispenser with at least one fuel pumping unit comprised of a fuel pump and a flow meter as well as a computer with display unit. The fuel dispensing takes place via one or a plurality of fuel hoses. The invention relates also to a method for operating such a device.
In fuel dispensers known from practice it is necessary to provide for each type of fuel, for example, regular gasoline, premium unleaded, premium, diesel or low-sulfur diesel, a separate fuel hose because each fuel hose contains only one flow channel for the fuel via which the fuel, coming from the fuel supply line, is guided at each fuel dispenser to the fuel nozzle through which the customer can dispense the fuel of the fuel dispenser.
It is furthermore known in fuel dispensing devices with vapor return to return the vapors, displaced from the tank to be filled, simultaneously to the filling of the vehicle fuel tank via the flexible fuel hose into the underground tank. For this purpose, the fuel hose is comprised of two coaxially arranged hoses inserted into one another whereby the inner hose serves for returning the vapors exiting from the tank to be filled while the coaxially arranged outer hose guides the fuel. The use of a respective hose for each type of fuel is, on the one hand, very expensive and, on the other hand, requires a large amount of space when up to five fuel hoses are arranged adjacent to one another at each fuel dispenser.
It is therefore an object of the present invention to provide a dispensing system for fuels for a device of the aforementioned kind that is economical to produce and flexible. A further object of the invention is to provide a method for operating such a dispensing system which ensures a simple and safe activation of the system.